Highly active electrocatalysts of CeO2 modified NiMoO4 nanosheet arrays towards water and urea oxidation reactions

Efficient anodic electrocatalysts are of great importance for the water and urea electrolysis to lower the overall potential for hydrogen generation. NiMoO4 is recently considered as a promising electrocatalyst towards water and urea oxidation reactions while its catalytic properties are still not comparable to the state-of-the-art catalysts. Herein, decorating CeO2 nanoparticles on NiMoO4 nanosheets is proposed and realized by the facile post-annealing treatment of NiMoO4 with absorbed Ce3+ ions. Due to the strong interaction between CeO2 and NiMoO4, the surface chemical states are modulated with more defects as catalytic sites. By optimizing the ratio of CeO2 to NiMoO4, the obtained catalyst of CeO2 modified NiMoO4 exhibited significantly enhanced activity with lower overpotentials and remarkable durability as compared with NiMoO4 for water and urea oxidation. Therefore, this facile method of post decorating CeO2 nanoparticles promoted the activity of NiMoO4, contributing to the robust anodes for low-cost and stable hydrogen generation.